A.N. Pirozhkov

New measurement of the electric dipole moment of the neutron

Abstract A new experiment on the search for the electric dipole moment of the neutron was carried out using a magnetic resonance set-up with electric field and stored ultracold neutrons. The EDM of the neutron was measured to be +(2.6±4.2±1.6)×10−26 e cm, the first error being RMS or statistical and the second one systematical. An upper limit at the 95% CL is |dn|

A new experimental study of the circular polarization of np capture γ-rays

Abstract An installation using a light-water neutron trap in the reactor core as a proton target is described. Results of the main and control measurements are presented which permit one to conclude that the parity-violating circular polarization of the γ-rays from the np → d γ reaction is P γ = (1.8 ± 1.8) × 10 −7 .

Search for an Electric Dipole Moment of the Neutron

The result of measuring the electric dipole moment (EDM) of the neutron by using ultracold neutrons is presented. The results of the measurements give the value of the EDM: d/sub n/4=(plus-or-minus7.5) x 10/sup -25/ excm. Hence, it can be concluded that vertical-bardvertical-bar<1.6 x 10/sup -24/ excm at the 90% confidence level.

Observation of parity violating effects in the polarized thermal neutron total and radiative capture cross sections of 117Sn and 139La

Abstract Parity violating effects in the transmission and radiative capture of longitudinally polarized thermal neutrons have been observed for 117 Sn and 139 La targets. Helicity dependent asymmetries a = 10 6 ( σ + -− σ − )/( σ + + σ − ) were found in the total cross section of 117 Sn ( a = 6.2 ± 0.7) and 139 La (a = 9.0 ± 1.4) , and also in the (n, γ) cross section of 117 Sn ( a = 22.6 ± 1.9) and of 139 La ( a = 16.1 ± 2.0).

Circular polarization of γ-quanta in np→dγ reactions with polarized neutrons

Abstract The circular polarization of the 2.23 MeV γ -quanta in the reaction np→d γ with polarized cold neutrons has been measured to be P γ =(−1.5±0.3)×10 −3 . A high-purity solid parahydrogen target was used. The circular polarization was measured with two magnetic transmission polarimeters, NaI(Tl) crystals with photomultipliers were used as detectors. The result is examined from the point of view of recent theoretical calculations.

Circular polarization of gamma quanta in the radiative capture of polarized thermal neutrons by protons

Abstract An experiment to measure the circular polarization of γ-quanta, P γ , in the reaction of radiative capture of polarized thermal neutrons by protons is described. Solid parahydrogen was employed as a proton target. The circular polarization was found to be P γ = −(2.90 ± 0.87) × 10 −3 which is in agreement with the theoretical estimates of P γ arising from the admixture of the triplet capturing state to the 1 S 0 principal capturing state.